TS/MP 2.5 System Management Manual

= LOG1 $0, EVENTFORMAT
= LOG2 LOGCOPY, STATUS
Before specifying a disk file for logging, you must first create that file, using the FUP CREATE
command. (You must ensure that the file is large enough.)
The PATHMON process records the log file names that you select in the PATHMON configuration
file. After a cool start, the same log files specified in the configuration file are used again; records
produced after the cool start are appended to these files.
If an error occurs while error information, status information, or both are being written to a log
file, the PATHMON process does:
1. Closes the log file specified with the file-name parameter.
2. Opens $0.
3. Writes the information to $0. The PATHMON process writes error information, status
information, or both to $0, depending on what was specified for the initial log file with the
STATUS parameter. Additionally, the PATHMON process writes the information to $0 in the
same format (that is, event messages or text) specified for the initial log file with the
EVENTFORMAT parameter.
If an error then occurs while information is being written to $0, the PATHMON process closes $0
and prohibits further error and status logging. The PATHMON process does not reopen either the
log file or $0.
In this example, you have configured two log files:
= LOG1 $0, EVENTFORMAT
= LOG2 $DATA.PM.LOGFILE, STATUS
If an error occurs on LOG1, the PATHMON process closes the log because the error occurred on
$0; the PATHMON process would not reopen LOG1. If an error occurs on LOG2, the PATHMON
process reopens $DATA.PM.LOGFILE as LOG2 $0, STATUS. The PATHMON process next sends
both error information and status information to $0 because although the LOG1 command did not
specify the STATUS parameter, the LOG2 command did. Additionally, the PATHMON process
sends both event messages and text messages to $0 because although the LOG2 command did
not specify the EVENTFORMAT parameter, the LOG1 command did.
NOTE: If the log file is running but is temporarily unavailable or overloaded, the PATHMON
environment might slow down.
Links and PATHMON Performance
A link is managed and owned by the PATHMON process that controls the server process. To
perform link management, PATHMON maintains status information for SERVER objects as well as
ACS subsystem processes. If your environment includes the Pathway/iTS product, the PATHMON
process also maintains status information for TCP and TERM objects.
By understanding how PATHMON manages links and what causes dissolution of links, you can
take steps to improve the performance of your system.
This can adversely affect PATHMON performance under exception conditions such as network or
processor failure:
• Maintaining object status to manage links
To manage links, the PATHMON process maintains status information about PATHMON
controlled objects and ACS subsystem processes. During exceptions, managing communication
100 Maintaining a PATHMON Environment